The subject matter herein relates generally to planar electronic devices, such as transformers, inductors, baluns, couplers, or fillers.
Some known electronic devices include planar bodies, such as circuit boards, that include one or more magnetic components built into the planar bodies. The magnetic component can include a ferrite core with conductive winding extending around the ferrite core. Some of these magnetic components include two conductive windings that are not conductively coupled with each other. For example, the conductive windings may not be physically or mechanically coupled such that electric current cannot flow through one conductive winding directly onto the other conductive winding. The current flowing through one winding generates a magnetic field in the core and in the other winding. The magnetic field in the other winding generates an electric current in the other winding. The electrical performance of the device can be determined by a variety of parameters, such as the ratio of the number of turns in the first winding to the number of turns in the second winding, the shape of the first and/or second windings, the impedance of the first and second windings, and the like.
The conductive windings typically include top conductors, bottom conductors, and conductive vias therebetween. Some planar electronic devices include circular ferrite cores, while other planar electronic devices include non-circular ferrite cores. The size and shape of the ferrite cores has an effect on density of the conductive windings as well as the layout of the conductive windings. Typically, the conductors making the windings are closely spaced to maximize capacitive coupling between adjacent windings. The layout of such conductors may have adjacent primary and secondary sections that are different (e.g. one short and one long), which negatively affects the performance of the planar electronic device. Additionally, some conductors suffer from degraded signals, such as from return loss. Furthermore, particularly at high frequency, planar electronic devices have poor performance compared to wired counterparts due to less primary and secondary capacitance.
A need exists for planar electronic devices having increased performance.